Comment Comment by joewalker I don't know if http://grepcode.com/file/repository.grepcode.com/java/root/j... is representative of all the implementations of bitCount in Java, but it's probably obvious that it's not going to use the popcnt opcode instruction.I think the point is that Rust makes it much easier to use that opcode instruction. It's possible but hard with GCC using __builtin_popcount(), but, I'd guess totally impossible in Java due to lack of a JVM instruction for the same. parent joewalker 9 years ago
I think the point is that Rust makes it much easier to use that opcode instruction. It's possible but hard with GCC using __builtin_popcount(), but, I'd guess totally impossible in Java due to lack of a JVM instruction for the same.